The present invention relates to a system for supplying fuel to a plurality of fuel injectors of a gas turbine engine. More particularly, the system is intended for use in gas turbine engines having aircraft applications.
At present, gas turbine engines in both civilian and military aircraft use incorporate fuel supply systems where the fuel to be consumed in the combustion chamber is supplied continuously by a simple fuel supply circuit. Fuel pumps feed the fuel to a fuel metering device and subsequently through a fuel distribution system which simultaneously supplies the metered fuel to all of the fuel injectors. The fuel metering device is suitably set by a drive means and the excess fuel is returned to the fuel pump intakes through a bypass flap valve, also set by the drive means. Since all of the injectors are supplied with fuel at low fuel flows, with low local richness in the combustion chamber, the combustion stability is difficult to achieve using these known systems.
U.S. Pat. Nos. 3,552,123 and 3,587,231 disclose sequential fuel control systems for jet engines in which a specified and predetermined number of fuel injectors are fed with fuel in a predetermined sequence. At low power outputs of the jet engine, the fuel distribution is not homogeneous.
U.S. Pat. No. 4,326,376 discloses a fuel supply system for a gas turbine engine in which fuel is supplied to the engine through three fuel flow regulating circuits in parallel between a common fuel intake aperture and a common fuel outlet aperture making it possible to simultaneously feed all of the fuel injectors.